One of the most common questions we hear before someone orders a quonset hut or arch steel building is simple: do I need a permit for this? The honest answer is that it depends — permitting is set at the state, county, and sometimes city level, and requirements vary widely across the country. Here's how to think through it, and what actually determines whether a permit applies to your project.
What Usually Triggers a Permit Requirement
While rules differ by jurisdiction, permit requirements are generally driven by a handful of common factors:
Whether the structure is permanent. Buildings set on a concrete foundation or footing are far more likely to require a permit than a temporary or fully portable structure.
Size and square footage. Many jurisdictions exempt small accessory structures (often under 120–200 square feet) from permitting, but larger buildings almost always require one.
Intended use. A residential accessory building, a commercial structure, and an agricultural building are frequently treated under different rules — agricultural exemptions in particular vary a lot by state and by whether the land is zoned for farm use.
Utility connections. Adding electrical, plumbing, or HVAC to the structure typically brings in additional permitting and inspection requirements beyond the building shell itself.
Local zoning. Setback requirements, lot coverage limits, and use restrictions are separate from the building permit itself but are checked as part of the same approval process in most areas.
Why "It Depends" Is the Honest Answer
Permitting authority in the U.S. sits primarily with state and local governments, not the federal government, and there's no single national standard for accessory or agricultural steel structures. A building that's permit-exempt in one county can require full plan review and engineering stamps in the next county over. Because of that, any article — including this one — that gave you a specific state-by-state checklist would be giving you outdated or incomplete information almost as soon as it was published, since local codes change.
What to Actually Do Before You Order
1. Call your local building or zoning department directly This is the only reliable source for your specific address — ask specifically about accessory structures, agricultural exemptions if relevant, and foundation requirements.
2. Ask what documentation they require for approval. Many jurisdictions require engineered building plans or a stamped engineering letter before they'll issue a permit.
3. Confirm wind and snow load requirements for your area. These numbers affect what's built into your structure's engineering, not just the paperwork.
How Duro Span Handles This
Every Duro Span building is engineered to meet the building code of the specific state and area it's being delivered to — not a generic national spec. When you order, we account for your local wind, snow, and seismic requirements as part of the engineering, and can provide the documentation most building departments ask for during the permit process. That doesn't replace a call to your local building department, but it means the building itself is designed to pass, not just to ship.
Not sure what your project will need? Call 888-848-2011 before you order — we can walk through what documentation is typically requested for your area and get your building engineered accordingly.